Taylor Casey case: FBI expert breaks down search for American woman missing in Bahamas

A retired FBI agent told Fox News Digital that new details surrounding the disappearance of the American woman who has been missing in Bahamas since June 19 is giving some "red flags."

As the search intensifies for Taylor Casey, a Chicago woman who disappeared on June 19 while on a yoga retreat in the Bahamas, a former FBI agent breaks down what steps the agency would take to aid in the effort.

"Is it possible that she's kidnaped and being held for ransom and somebody hasn't reached out yet? Those are hopeful, right? Because any day that you can say that my loved one is still alive … it's a good day," Scott Duffey, retired FBI supervisory special agent and co-director of Wilmington University Criminal Justice Institute, told Fox News Digital.

Royal Bahamas Police Force Chief Superintendent Chrislyn Skippings said Wednesday that Casey’s cellphone was found in the ocean, but her other belongings are still at the retreat, the Nassau Guardian reported. 

Now that investigators have Taylor's cellphone, Duffey said they will explore all possibilities, whether this is a criminal case or was an accident.

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Some examples he offered that investigators are looking into are: Did she go into the ocean for a swim and drowned, or did she go on a hike and fall, or did she get lost or was she the victim of a crime?

"Nine days is a long time to be missing," Duffey said. "If you went into the wilderness, if you went into the ocean, but if you don't have that exit, some piece of information to say I saw them come out or this or that, it will remain a search for her and hoping that she is alive."

Duffey said there are several factors that would take it from a search and rescue to a search and recovery. 

"Search and rescue is we want to locate somebody who is endangered but hoping that they're still alive. And so it's search and rescue, and then you see the transition to recovery. And of course, family and friends never want to hear recovery," Duffey explained. 

"Because until they have that one item to say there's where she was, so, for example, let's say she was out in the ocean hundreds of miles or many miles off. She goes over the boat and there's nothing else. Then at some point you can say, this is turning into a recovery. But until they get that piece, you know, nine days, it's a long time to be missing," Duffey continued.

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Duffey said the FBI would be involved on day one of her reported disappearance and that they would be working with Bahama authorities immediately upon request.

"[The] FBI handles all crimes against Americans overseas and can either assist the locals or look to prosecute here in the U.S. with that jurisdiction as the assist. This is why any terror attack in the world against a U.S. citizen can be prosecuted here," Duffey said.

"Once they determine it's most likely a mysterious disappearance, then the FBI gets triggered through the legal attaché office and the FBI office that handles that region of the world for all crimes against an American citizen," Duffey said.

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Duffey added that this case would have been handled similarly to the Natalee Holloway case in Aruba and the missing woman from Florida, Ana Maria Knezevich, who was believed to be killed by her Serbian husband in Argentina. 

Casey, 41, remains missing after being last seen at the Sivananda Ashram Yoga Retreat on Paradise Island in Nassau.  

Duffey said investigators are treating this case with urgency as each day Taylor is not found, it's less likely she'll be found alive.

Casey’s family said they are "deeply concerned" for her safety and well-being as the search continues. 

"I believe Taylor is in danger because she was eager to share her yoga retreat experience with others upon her return," Taylor's mother, Colette Seymore, said in a statement. "Taylor would never disappear like this."